(a) Technical Field of the Invention
The present invention relates to a lengthways stretchable elastic band structure, which allows an elastic band to stretch sideways as well as lengthways, thereby expanding the stretchable area of the elastic band. The invention can be applied to headgears such as headbands and cap bands for better fitting and functionality when worn by a user.
(b) Description of the Prior Art
When performing exercises, people often utilize a headband to hold their hair to prevent the hair from interfering their exercises, and to absorb sweat. Generally, a headband is made of fabrics that have good absorption, and is provided with a stretchable elastic band so that the headband can fit the user's head properly and comfortably. Such headband allows the user to easily put on and avoid the feeling of having something tied to his/her head.
As caps not only can serve the purposes of shading rain and sun, but also can be used to match clothing for various styles, they are popular amoung consumers.
Taking a cap structure for example, the conventional structure of a cap is provided with a peak made of soft plastic, the top of which is combined to a crown having an elastic band at the rear end. By way of the tension of the elastic band, the cap can be fitted to users of various head sizes. Therefore, the extensibility of the elastic band is an extremely important requirement of headgear products.
In the prior art under U.S. Pat. No. 6,625,818, the key point of the design thereof is an elastic band including layers of stretchable fabrics and elastic stitching, such that when the elastic band is pulled by force, the area thereof will expand. However, as the layers of fabrics are secured by the elastic stitching in a lengthways direction of the elastic band, the lengthways stretch ability of the elastic band is the smallest of all the fabrics and the stitching, which could be none since the fabrics may be uniaxially or multiaxially stretchable as disclosed in the patent specification.
Since the lengthways stretch ability of the elastic band is limited by the material, the choice of materials for the elastic band is also limited. When improper materials are selected and the lengthways stretch ability is poor, a user may feel restrained when wearing a wrong size elastic band on the head, and gradually feel stressed after a period of time.
Accordingly, the inventor has a motive to improve the elastic bands of the prior art to allow the user to wear the elastic band products, such as headbands and headgears, comfortably without feeling restrained or stressed.